S Aksoy

Center for Assisted Reproduction, Bedford, Texas, United States

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Publications (25)90.26 Total impact

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    ABSTRACT: Endometrioma surgery by stripping the cyst capsule has been associated with a reduction in ovarian reserve. It is still not clear whether the inflicted damage is immediate, sustained over time or associated with the use of electrocautery, nor which marker is more accurately reflects the post-operative reduction in ovarian reserve. This observational study assessed the damage inflicted by endometrioma removal with anti-Müllerian hormone (AMH) concentration and antral follicle count (AFC) pre and post-operatively. Twenty-five women with unilateral endometrioma underwent laparoscopic stripping of the endometrioma cyst capsule. There was a significant decrease both in AMH concentration (24%) and in AFC (11%) 1 month following surgery (P<0.01). At 6months post-operatively, the respective values were 24% and 15% less than preoperatively. AMH concentration and AFC showed no correlation with the use of bipolar electrocautery during surgery. Primordial follicles embedded adjacent to the cyst capsule were found in 61.5% of the specimens. Endometrioma surgery by stripping of the cyst capsule is associated with a significant reduction in ovarian reserve. The reduction is immediate and sustained over time. AMH appears to be a better indicator for post-operative quantification of the ovarian reserve. Endometrioma surgery by stripping the cyst capsule has been associated with a reduction in ovarian reserve. It is still not clear whether the inflicted damage is immediate, sustained over time or associated with the use of electrocautery, nor which marker more accurately reflects the post-operative reduction in ovarian reserve. In this observative study, we assessed the damage inflicted by endometrioma removal with anti-Müllerian hormone (AMH) and antral follicle count (AFC) pre- and post-operatively. Twenty-five women underwent laparoscopic stripping of the endometrioma cyst capsule. There was a 24% decrease in AMH concentration and an 11% decrease in AFC compared with the preoperative values 1month following surgery. The values did not change 6months after surgery over those recorded at 1month post-operatively (24 and 15% less than preoperative values. Primordial follicles embedded adjacent to the cyst capsule were found in 61.5% of the specimens. Endometrioma surgery by stripping of the cyst capsule is associated with a significant reduction in ovarian reserve. The reduction is immediate and sustained over time. AMH appears to be a better indicator for post-operative quantification of the ovarian reserve.
    Reproductive biomedicine online 05/2013; · 2.68 Impact Factor
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    ABSTRACT: Although, it is well known that pre-incubation of oocytes prior to conventional IVF improves fertilization and pregnancy rates, there are conflicting results regarding the effect of pre-incubation time in ICSI. This study evaluated the role of pre-incubation of oocytes on outcome in intracytoplasmic sperm injection (ICSI) cycles. A total of 1260 patients undergoing their first ICSI cycles were evaluated retrospectively. In patients undergoing ICSI during the year 2000 (Group I, n = 670), oocytes were injected immediately after retrieval, whereas in patients undergoing ICSI during 2001 (Group II, n = 590), oocytes were incubated for 2-4 h prior to injection. The mean age of patients was 33.9 +/- 5.04 years and 34.1 +/- 5.06 years in groups I and II, respectively. The number of oocytes with a first polar body (MII) and fertilization and cleavage rates were higher, and embryo quality was significantly better in group II. In contrast, the total numbers of oocytes without a first polar body (MI), those where germinal vesicle breakdown had not occurred (GV), and empty zona oocytes were higher in group I. No difference was found in the number of embryos transferred or implantation or clinical pregnancy rates. This study demonstrated that pre-incubation of oocytes prior to ICSI is associated with improved maturation of oocytes, fertilization and embryo quality.
    Reproductive biomedicine online 07/2004; 8(6):682-6. · 2.68 Impact Factor
  • Fertility and Sterility - FERT STERIL. 01/2003; 80:203-203.
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    ABSTRACT: To compare the outcome of zona-intact versus zona-free blastocyst transfer. Prospective, randomized study. Tertiary care private hospital IVF center. A total of 240 patients undergoing blastocyst stage ET (119 zona intact and 121 zona free). In vitro culture of embryos to the blastocyst stage was followed by random allocation to zona-intact or zona-free transfer. Treatment cycle characteristics, implantation, and pregnancy rates. Transfer of zona-free blastocysts was associated with a higher implantation rate. Subgroup analysis, however, indicated that better outcome was achieved only in the group that received poor-quality blastocysts. Patients undergoing blastocyst transfer for the first time did not seem to benefit from zona-free blastocyst transfer. Zona-free blastocyst transfer increases the success of blastocyst-stage transfer in patients with poor-quality blastocysts.
    Fertility and Sterility 09/2002; 78(2):392-6. · 4.17 Impact Factor
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    ABSTRACT: To evaluate the relationship between embryo cleavage time and implantation and pregnancy rates in women undergoing intracytoplasmic sperm injection (ICSI) for male factor infertility. A total of 78 patients undergoing their first ICSI cycle were evaluated prospectively. Embryos were assessed for early cleavage to the two-cell stage 27 hours after injection. Early cleavage of at least one embryo was observed in 48 cycles (group I). None of the embryos cleaved early in the remaining 30 cycles (group II). There was no difference regarding mean patient age, duration of ovarian stimulation, number of gonadotropin ampules used, number of oocytes retrieved, fertilization, cleavage rates and embryo quality between the two groups. Implantation and clinical pregnancy rates were significantly higher in group I than II (17.9% and 45.8% vs. 5.1% and 16.7%, respectively; P < .05). Furthermore, progression to the blastocyst stage in excess embryos was significantly higher in group I than II (56.7% vs. 25.0%, P < .05). Pregnancy and implantation rates were higher in patients who have early cleaving embryos; absence of early cleavage was associated with a poor outcome.
    The Journal of reproductive medicine 07/2002; 47(7):540-4. · 0.75 Impact Factor
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    ABSTRACT: Intracytoplasmic injection of testicular round spermatids has been suggested as a salvage treatment in couples when testicular sperm extraction does not yield any mature sperm. However, the success of the procedure is debatable, and controversy surrounds issues such as the presence and (if present) identification of spermatids in testicular tissue. Progression rate to the blastocyst stage of spermatid-derived embryos appears to be low. In this study, we investigated the feasibility and outcome of blastocyst stage embryo transfer after round spermatid injection (ROSI). ROSI was undertaken in 58 couples who did not yield mature or elongated sperm to testicular sperm extraction. The incidence of blastocyst formation from two pronuclear oocytes was 7.6%. A total of 16 blastocysts were transferred in 12 patients (20.7%). None of the patients conceived. The results of this study indicate that the blastocyst stage is reached by only very few ROSI-derived embryos and these embryos do not implant.
    Human Reproduction 04/2002; 17(3):741-3. · 4.67 Impact Factor
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    ABSTRACT: Embryo quality may be accurately assessed as early as the pronuclear zygote phase, as shown in recent studies. However, it is not known whether good quality zygotes are destined to become good quality cleavage stage embryos and blastocysts. In this retrospective study, 86 intracytoplasmic sperm injection-embryo transfer cycles were studied where each available embryo was scored from the zygote until the blastocyst stage. Embryonic normality parameters such as pronuclear pattern, early cleavage, cleavage stage embryo grade, the presence of embryos with > or =8 cells on day 3 and blastocyst quality were recorded. Embryo transfer was undertaken at the blastocyst stage and the outcome was studied according to the pronuclear pattern exhibited by the zygotes. Embryos that showed an ideal pronuclear pattern (0 PN pattern) cleaved earlier and faster and resulted in better quality cleavage stage embryos and blastocysts. The incidence of blastocyst formation was 72% in zygotes showing a 0 PN pattern, compared with 12.7% in zygotes with double pronuclear abnormality. Higher implantation and pregnancy rates were obtained when at least one blastocyst derived from a 0 PN pattern zygote was included in the set of embryos to be transferred. Our results indicate that the pronuclear pattern of the zygote is closely related to blastocyst formation and quality. Blastocysts derived from 0 PN zygotes have a higher potential for implantation.
    Human Reproduction 12/2001; 16(11):2357-61. · 4.67 Impact Factor
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    ABSTRACT: To determine the feasibility and success of blastocyst-stage embryo transfers in patients having only fair and poor quality cleavage-stage embryos on day 3. Prospective case study with historic controls. Tertiary care private hospital IVF center. A total of 158 day 5 embryo transfer cycles in patients with grade 3 and grade 4 cleavage-stage embryos. Control group consisted of 162 day 3 transfer cycles performed with embryos of similar quality. In vitro culture of embryos up to the blastocyst stage. The percentage of cycles that culminated in the transfer of at least one blastocyst and implantation and pregnancy rate related to the day of transfer. In the day 3 transfer group, a mean of 5.2 embryos were replaced per patient. This was significantly more than the mean of 2.4 embryos that could be replaced on day 5 (P <.001). The clinical pregnancy rate per embryo transfer was 27.2% and 33.5% in the two groups, respectively (P >.05). The implantation rate per embryo was significantly higher in the day 5 transfer group (15% vs. 5.9%). The multiple pregnancy and abortion rates were similar between the groups. Transfer of fair and poor quality embryos at the blastocyst stage is feasible and is associated with higher implantation rates as compared to transfer of similar quality embryos on day 3.
    Fertility and Sterility 04/2001; 75(3):514-8. · 4.17 Impact Factor
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    ABSTRACT: Recent studies indicate a strong paternal influence on embryo development and progression of the embryo to the blastocyst stage. The aim of this study was to compare, during extended culture, the in-vitro development of embryos resulting from intracytoplasmic sperm injection (ICSI) of ejaculated spermatozoa (group 1, n = 347), epididymal (group 2, n = 22) or testicular (group 3, n = 18) spermatozoa from obstructive azoospermic and testicular spermatozoa from non-obstructive azoospermic (group 4, n = 31) subjects. Fertilization and blastocyst formation rates were significantly lower in group 4 (P < 0.05). The incidence of expanded and hatching blastocysts was significantly lower in group 4 (P < 0.05). Overall in 93.2% ejaculate ICSI cycles, blastocysts were transferred on day 5. This was significantly higher than the 62% day 5 transfers in the non-obstructive azoospermic group (P < 0.05). Implantation rate per embryo was significantly higher in the ejaculate ICSI group compared with the other groups (P < 0.05). Clinical pregnancy per transfer was similar between groups; however, significantly fewer multiple pregnancies were encountered in the non-obstructive azoospermic group (P < 0.01). In conclusion, the source of the spermatozoa, most likely to be indicative of the severity of spermatogenic disorder, affects the rate of blastocyst formation and blastocyst implantation. Spermatozoa from non-obstructive azoospermic subjects, when utilized for ICSI, result in embryos that progress to the blastocyst stage at a lower and slower rate and implant less efficiently.
    Human Reproduction 02/2001; 16(1):125-129. · 4.67 Impact Factor
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    ABSTRACT: To determine the relationship between blastocyst quality and the results of embryo transfer at the blastocyst stage. Retrospective case analysis. Tertiary care private hospital IVF center. A total of 350 blastocyst-stage embryo transfer cycles. In vitro culture to the blastocyst stage was undertaken in 350 ICSI cycles where four or more cleavage-stage embryos were available on day 3. Relationship between blastocyst quality and implantation and clinical and multiple pregnancy rates. Transfer of at least one grade 1 or grade 2 blastocyst or one hatching blastocyst was associated with very high implantation and pregnancy rates. However, transfer of grade 3 blastocysts yielded very low implantation and pregnancy rates. There appears to be a strong correlation between blastocyst quality and success of blastocyst transfer.
    Fertility and Sterility 09/2000; 74(2):282-7. · 4.17 Impact Factor
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    ABSTRACT: We have shown previously that germ cells recovered from some men with maturation arrest can resume spermatogenesis in vitro and give rise to late elongated spermatids. This study relates the ability of germ cells to differentiate in vitro to the stage at which spermatogenesis is blocked in vivo and to the patient's serum FSH concentration. The presence of germ cells at different stages of spermatogenesis was assessed, before and after culture, by classical cytology, by fluorescence in-situ hybridization and by immunocytochemistry with a germline-specific marker. The proportion of cases of maturation arrest at the primary spermatocyte, secondary spermatocyte and spermatid stage in which in-vitro resumption of meiosis was achieved was 24.3% (9/37), 100% (3/3) and 51.1% (23/45) respectively. Serum FSH concentrations were higher than normal in most cases. However, lower values were measured in patients in whom in-vitro spermatogenesis was achieved compared with those in whom no progression was detected. These data show that, under the conditions of this study, germ cells from men with very high serum FSH concentrations (>20 IU/l) are less likely to resume spermatogenesis in vitro than those coming from men with only moderate increase (10-20 IU/l).
    Human Reproduction 07/2000; 15(6):1350-4. · 4.67 Impact Factor
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    ABSTRACT: Progression to the blastocyst stage of embryos derived from testicular round spermatids in men with non-obstructive azoospermia was studied. A total of 56 men were studied in whom partial spermatogenesis failure had occurred where only very few spermatozoa (fewer than the number of oocytes retrieved) were extracted from multiple testicular biopsy specimens. Oocytes remaining after intracytoplasmic injection of testicular spermatozoa (group 1) were injected with round spermatids (ROSI, group 2). Only embryos derived from group 1 were transferred. Remaining embryos were observed under culture for 8 days and their progression to the blastocyst stage was recorded. Of the 546 oocytes injected with testicular spermatozoa, 404 (73.9%) showed evidence of 2-pronuclear (2PN) fertilization. Injection of testicular round spermatids resulted in 2PN fertilization rate of 50% (P < 0.05). Using a four-point grading system, 53% of the good quality embryos (grade 1 or 2) in group 1 reached the blastocyst stage compared with 25% in group 2 (P < 0.05). The rate of progression to the blastocyst stage of grade 3 and grade 4 embryos was 46 and 8.5% in the two groups respectively (P < 0.05). Using a different three-point grading system for the blastocysts, 75.3% of the blastocysts in group 1 were either grade 1 or grade 2 and 24.7% were grade 3. However, in group 2 all blastocysts were grade 3. All embryos observed in group 1 reached the blastocyst stage by day 5 or 6 compared with 25% of the embryos reaching the blastocyst stage by this time in group 2. While 31.2% of the blastocysts in group 1 showed evidence of spontaneous hatching in vitro, none of the blastocysts in group 2 hatched. In conclusion, progression to the blastocyst stage occurred at a much lower and slower rate in embryos derived from testicular round spermatids. Furthermore, all blastocysts resulting from ROSI were of poor quality and none showed spontaneous hatching. These results may explain the dismal outcome associated with ROSI.
    Human Reproduction 07/2000; 15(6):1377-82. · 4.67 Impact Factor
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    ABSTRACT: The aim of this study was to evaluate whether the extraction of testicular spermatozoa with percutaneous versus open biopsy has an effect on the treatment outcome with intracytoplasmic sperm injection (ICSI) in men with non-obstructive azoospermia. Regardless of testicular size, follicle stimulating hormone concentration, and previous biopsy result, percutaneous testicular sperm aspiration (PTSA) using a 21-gauge butterfly needle was attempted first and if this failed testicular sperm extraction (TESE) was performed. In 63 men spermatozoa were found with PTSA whereas in 228 men TESE had to be undertaken. More men in the PTSA group had previously been diagnosed with hypospermatogenesis (82 versus 50%). Compared with the PTSA group, more men in the TESE group had germ cell aplasia (27 versus 10%) or maturation arrest (22 versus 8%). There was no difference between the groups regarding mean age of men and their partners, duration of stimulation, oestradiol concentration on the day of human chorionic gonadotrophin, number of oocytes retrieved, fertilization rate, and embryo quality between the two groups. The number of embryos transferred (4.38 versus 3.90) was significantly higher in the PTSA group (P < 0.05), reflecting the increased number of embryos available for transfer. Implantation rate per embryo was 20.7% in the PTSA and 13.3% in the TESE group (P < 0.05). Clinical pregnancy rates were 46 and 29% in the PTSA and TESE groups respectively (P < 0.05). Clinical abortion rates were similar (21.2 versus 24%). It is concluded that in men with non-obstructive azoospermia, easier sperm retrieval, which is most likely indicative of a more favourable histopathology, is associated with higher implantation rates per embryo.
    Human Reproduction 07/2000; 15(7):1548-51. · 4.67 Impact Factor
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    ABSTRACT: To analyze the performance of two different embryo transfer catheters (Wallace and Frydman) in an in vitro fertilization (IVF)-intracytoplasmic sperm injection (ICSI) program. Four hundred twenty-eight IVF or ICSI embryo transfer cycles were analyzed. A trial transfer was performed before the initiation of controlled ovarian hyperstimulation to determine the choice of embryo transfer catheter, Wallace or Frydman. Actual transfer was undertaken with the catheter chosen from the trial transfer. During actual embryo transfer, 214 (93.5%) of the intended 229 Wallace transfers were successful, and in 15 transfers the Frydman catheter was used. Of the intended 199 Frydman transfers, all were successful. Clinical pregnancy rate, implantation rate per embryo and ectopic pregnancy rate per transfer for the Wallace catheter were 41.6%, 16% and 0.9%, respectively. Respective rates for the Frydman catheter were 36.0%, 14.4% and 0.9% (P > .05 for all variables). Trial catheterization prevented most of the unanticipated procedural difficulties during the actual transfer. Both Wallace and Frydman catheters performed similarly, although there was a slight but nonsignificant increase in clinical pregnancy rates with the Wallace catheter.
    The Journal of reproductive medicine 02/2000; 45(2):135-8. · 0.75 Impact Factor
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    ABSTRACT: To evaluate the association between serum P levels on the day of hCG administration and the outcome of intracytoplasmic sperm injection (ICSI). Retrospective case study. Assisted reproduction unit of a tertiary care private hospital. Nine hundred eleven ICSI cycles that proceeded to ET were studied. The decision to administer hCG was based on serum E2 levels and follicle size. Serum P was measured from frozen sera obtained on the day of hCG administration. Cycles were stratified according to serum P levels of <0.9 ng/mL (n = 298) or > or =0.9 ng/mL (n = 613). This cutoff level was selected because it yielded the highest sensitivity and specificity according to a receiver operator characteristic curve. Implantation and clinical pregnancy rates. In cycles with high serum P levels, more oocytes were retrieved and more embryos were available for transfer. Clinical pregnancy rates per ET in the low and high P groups were 36.9% and 45.4%, respectively (P<.05). The implantation rate per embryo was similar in the two groups (14.9% and 16.4%, respectively, in cycles with P levels <0.9 vs > or =0.9 ng/mL). Abortion rates were 22.7 and 25.8%, respectively (P>.05). Our data showed no adverse effect of high serum P levels on the day of hCG administration on implantation rates after ICSI and ET.
    Fertility and Sterility 01/2000; 72(6):975-9. · 4.17 Impact Factor
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    ABSTRACT: The aim of this study was to determine the effect of 24-h in-vitro culture of testicular spermatozoa in recombinant follicle stimulating hormone (recFSH) supplemented medium versus simple medium on sperm motility, and to analyse the outcome of intracytoplasmic sperm injection (ICSI) of such spermatozoa. A total of 143 positive testicular sperm extraction procedures in men with non-obstructive azoospermia was evaluated prospectively. Extracted testicular tissue samples were randomized to be cultured in vitro for 24 h in simple medium or recFSH supplemented media. ICSI was performed with spermatozoa cultured in recFSH (n = 73) or in simple medium (n = 70). Sperm motility following in-vitro culture, embryo quality after ICSI, and implantation and pregnancy rates were assessed. Of the 898 MII oocytes available in the recFSH group, 646 (71.9%) were injected with spermatozoa showing either twitching or progressive motility. However, only 29.1% of the oocytes in the simple medium group (245/841) were injected with motile spermatozoa (P < 0.05). Fertilization rate (68.8 versus 42.1%), implantation rate per embryo (20.1 versus 13.2%), and clinical pregnancy rate (47. 9 versus 30%) were significantly increased in the recFSH group compared with the simple medium group respectively (P < 0.05). In conclusion, in-vitro culture with recFSH appears to increase the motility of testicular spermatozoa, thus increasing the success of ICSI.
    Human Reproduction 11/1999; 14(11):2808-11. · 4.67 Impact Factor
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    ABSTRACT: In this study, we compared the fertilization rate and embryo quality after intracytoplasmic sperm injection (ICSI) as they relate to oocyte morphology. A total of 654 ICSI cycles yielding 5903 metaphase II oocytes were observed. The oocytes retrieved in these cycles were divided into (i) normal oocytes, (ii) oocytes with extracytoplasmic abnormalities (dark zona pellucida and large perivitelline space), (iii) oocytes with cytoplasmic abnormalities (dark cytoplasm, granular cytoplasm, and refractile body), (iv) oocytes with shape abnormalities, and (v) oocytes with more than one abnormality (double and triple abnormalities). Intracytoplasmic vacuoles and aggregates of smooth endoplasmic reticulum were not recorded separately. The fertilization rate and quality of morphologically graded embryos did not differ between the groups. There were 77 cycles where all transferred embryos were derived from abnormal oocytes, and 164 cycles where all embryos were derived from normal oocytes. These cycles were studied further. The two groups were comparable regarding mean female age, duration of infertility, duration of ovarian stimulation, number of ampoules of gonadotrophin injected, and number of oocytes retrieved. Two clinical pregnancy rates (44.4 versus 42.1%) and implantation rates per embryo (10.3 versus 13.2%) were similar. In conclusion, in couples undergoing ICSI, abnormal oocyte morphology is not associated with a decreased fertilization rate or unfavourable embryo quality. Furthermore, embryos derived from abnormal oocytes yield similar clinical pregnancy and implantation rates when transferred compared with embryos derived from normal oocytes.
    Human Reproduction 01/1999; 13(12):3431-3. · 4.67 Impact Factor
  • Fertility and Sterility 12/1998; 70(5):983-4. · 4.17 Impact Factor
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    ABSTRACT: A prospective study was performed to determine the feasibility of evaluating the uterine cavity by sonohysterography (SHG) in women who were scheduled for intracytoplasmic sperm injection (ICSI) due to severe male factor infertility and who had not had a previous hysterosalpingography (HSG). Sonohysterography was performed in 80 women scheduled for ICSI. A subsequent hysteroscopy was undertaken in patients with intracavitary lesions. The outcome of ICSI for the women undergoing SHG was compared with that of 240 cycles performed (during the same time period) in patients who had a normal HSG before admission to the clinic. There were no complications attributable to the SHG procedure. Hysteroscopy correctly identified all lesions depicted by SHG. SHG and HSG groups were comparable with regard to female age and duration of infertility. Clinical pregnancy rates per transfer were 40.2% and 42.5% in the SHG and HSG groups, respectively. Abortion rates in the two groups were also similar (14.8 and 11.0%, respectively). In conclusion, sonohysterography appears to be a simple, inexpensive, and safe alternative to HSG for evaluation of the uterine cavity in women scheduled for ICSI.
    Human Reproduction 10/1998; 13(9):2461-2. · 4.67 Impact Factor
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    ABSTRACT: Excess embryos from patients undergoing intracytoplasmic sperm injection and embryo transfer for male infertility were cultured to determine the rate and timing of their progression to the blastocyst stage. In 194 embryo transfer cycles, four embryos with the morphologically best grading were transferred and at least two embryos were cultured. The cycles were classified as: group 1: no excess embryos reached blastocyst stage, group 2: >50% of embryos reached blastocyst stage by days 4-5, group 3: <50% of embryos reached the blastocyst stage by days 4-5, group 4: >50% of the embryos reached blastocyst stage by days 6-7, group 5: <50% of the embryos reached blastocyst stage by days 6-7. All groups were similar regarding female age, duration of infertility, and parameters of ovarian stimulation. In group 1, clinical pregnancy and implantation rates were 14 and 11% respectively, and were similar to those of group 4. In group 2, clinical pregnancy and implantation rates were 75 and 33%. Multiple implantations occurred in 81% of group 2 or 3 cycles, compared to none in group 1 cycles. The results suggest that the development potential of the embryo is intrinsic, and that embryos which carry a high potential for development yield a high clinical pregnancy rate and multiple implantations.
    Human Reproduction 09/1998; 13(9):2564-7. · 4.67 Impact Factor